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1.
S N Walters T A Reinhardt M A Dominick R L Horst E T Littledike 《Archives of biochemistry and biophysics》1986,246(1):366-373
In order to investigate the subcellular distribution of unoccupied 1,25-dihydroxyvitamin D3 receptors, highly purified cytoplasts and nucleoplasts were prepared from two kidney cell lines (PK1 and MDBK). This was accomplished utilizing the technique of enucleation by cytochalasin B and density gradient centrifugation. Unoccupied 1,25-dihydroxyvitamin D3 receptors were found in both the nuclear and cytosolic compartments, with approximately 70% of the receptors localized in the cytoplasm. When cells were pretreated with 1,25-[3H]dihydroxyvitamin D, prior to enucleation, it was found that 90% of the receptor-hormone complex was associated with nucleoplasts, thus demonstrating that cytochalasin B treatment does not alter the high-affinity association of the receptor-hormone complex with the nucleus. The ratio of unoccupied receptor/protein was found to be the same in whole cells, cytoplasts, and nucleoplasts for both cell types. The ratio of unoccupied receptor/DNA was highest in cytoplasts and lowest in nucleoplasts. Taken together, these data indicate that the unoccupied 1,25-dihydroxyvitamin D receptor is generally associated with cell proteins and not specifically associated with cell DNA. We therefore propose, at least for these cells, that the unoccupied 1,25-dihydroxyvitamin D receptor exists in equilibrium between the nuclear and cytosolic compartments of the whole cell, and receptor-hormone binding shifts this equilibrium to favor nuclear localization. 相似文献
2.
Intratracheal instillation of a novel NO/nucleophile adduct selectively reduces pulmonary hypertension 总被引:1,自引:0,他引:1
Brilli Richard J.; Krafte-Jacobs Brian; Smith Daniel J.; Roselle Dominick; Passerini Daniel; Vromen Amos; Moore Lori; Szabo Csaba; Salzman Andrew L. 《Journal of applied physiology》1997,83(6):1968-1975
Brilli, Richard J., Brian Krafte-Jacobs, Daniel J. Smith,Dominick Roselle, Daniel Passerini, Amos Vromen, Lori Moore, CsabaSzabó, and Andrew L. Salzman. Intratracheal instillation ofa novel NO/nucleophile adduct selectively reduces pulmonary hypertension. J. Appl. Physiol. 83(6):1968-1975, 1997.We examined the pulmonary and systemichemodynamic effects of administering soluble nitric oxide (NO) donorcompounds (NO/nucleophile adducts, i.e., NONOates) directly into thetrachea of animals with experimentally induced pulmonary hypertension.Steady-state pulmonary hypertension was created by using thethromboxane agonist U-46619. Yorkshire pigs were randomly assigned toone of four groups: group 1,intratracheal saline (control; n = 8);group 2, intratracheal sodiumnitroprusside (n = 6);group 3, intratracheal ethylputreanineNONOate (n = 6); andgroup 4, intratracheal2-(dimethylamino)-ethylputreanine NONOate (DMAEP/NO;n = 6). Pulmonary and systemichemodynamics were monitored after drug instillation.Group 4 had significant reductions in pulmonary vascular resistance index (PVRI) at all time points comparedwith steady state and compared with group1 (P < 0.05), whereas systemic vascular resistance index did not change. The meanchange in mean pulmonary arterial pressure in group4 was 33.1 ± 1.2% compared with +6.4 ± 1.3% in group 1 (P < 0.001), and the mean change inmean arterial pressure was 9.3 ± 0.7% compared with acontrol value of 0.9 ± 0.5%(P < 0.05). Groups 2 and 3 hadsignificant decreases in both PVRI and systemic vascular resistanceindex compared with steady state and with group1. In conclusion, intratracheal instillation of apolar-charged tertiary amine NONOate DMAEP/NO results in the selectivereduction of PVRI. Intermittent intratracheal instillation of selectiveNONOates may be an alternative to continuously inhaled NO in thetreatment of pulmonary hypertension. 相似文献
3.
Dominick J. Paolillo Jr. 《American journal of botany》1982,69(6):1032-1042
This paper deals with a comparison of the rooted axes (rhizomorphs) of Isoetes with those of Stigmaria, Pleuromeia and other fossil lycopsids from the standpoint of developmental correspondence. The objective is to present a mechanistic approach to the problem of evaluating possible interrelationships among the genera. The results complement those from other comtemporary approaches to the same problem. These main points are advocated: 1) The rhizomorphs of Isoetes and Stylites correspond. Because neither of these contains an apical meristem, neither corresponds to Stigmaria with respect to organization of the axis or root production. 2) Rooted portions of Isoetes and Pleuromeia correspond, although external lobing in Pleuromeia parallels lobing of the stele, whereas in Isoetes external lobing occurs between the lobes of the stele. In both cases, lobing of the stele is associated with root production. 3) Paurodendron rhizomorphs appear to correspond to Stigmaria developmentally with regard to the presence of an apical meristem and the arrangement of roots, but Paurodendron rhizomorphs are shorter. If several lines of root production were added to the vascular cambium of the kind of rhizomorph seen in Paurodendron, a plant part like the rooted portion of Pleuromeia could result. Further extrapolations of the Paurodendron form of growth are explored for their bearing on comparison of rhizomorphs among the lycopsids. 相似文献
4.
Eukaryotic genes are usually replicated early during S-phase in the cell lineages in which they are expressed. Using partially characterized cDNA probes, we recently established two exceptions to this rule in the slime mold Physarum polycephalum. In this paper, we analyzed the structure and the identity of one of these two genes. By genomic cloning and Southern analysis we demonstrate that it is a single-copy gene and decipher the structure of the two alleles by taking advantage of a restriction fragment length polymorphism. By cDNA cloning and sequencing, we deduced the amino acid coding capacity of the mRNA. Finally, we confirmed the late replication of this abundantly expressed gene by "gene dosage" analysis, an experiment that did not require any drug treatment of the cell. Our results provide for the characterization and the structure of the first developmentally regulated gene known to be replicated late in S-phase and abundantly expressed within a eukaryotic cell. 相似文献
5.
C. Anthony Altar Mark Armanini Millicent Dugich-Djordjevic Gregory L. Bennett Regina Williams Shamiram Feinglass Vince Anicetti† Dominick Sinicropi Charles Bakhit 《Journal of neurochemistry》1992,59(6):2167-2177
Polyclonal antibodies against recombinant human nerve growth factor (rhNGF) potently inhibited PC12 neurite outgrowth, blocked high-affinity 125I-rhNGF binding but not its receptor, and cross-reacted with rat, mouse, and human nerve growth factor (NGF) but not with brain-derived neurotrophic factor, neurotrophin-3, ciliary neurotrophic factor, insulin-like growth factor, epidermal growth factor, or activin A. Immunocytochemistry revealed many NGF-positive neurons in the rat neostriatum. The NGF-positive neurons disappeared by 3 days after mechanical injury to the neostriatum and were replaced by intensely NGF- and glial fibrillary acidic protein-positive astrocytes. Enzyme-linked immunosorbent assay measurements revealed that the NGF content of the injured striatum was elevated by eightfold 3 days postinjury and by twofold 2 weeks later. The high-affinity choline uptake (HACU) into cholinergic nerve terminals was decreased by 23% at 2 and 4 weeks postinjury, yet choline acetyltransferase (ChAT) activity in these neurons was unchanged at 2 weeks and decreased by 14% at 4 weeks. Daily infusion of 1 microgram of rhNGF into the injury area did not alter the loss of HACU. However, this treatment elevated ChAT activity by 23-29% above intact neostriatal levels and by 53-65% relative to HACU at both survival times. Thus, lesion-induced increases in NGF levels within astrocytes are associated with maintenance of striatal ChAT activity at normal levels following cholinergic injury, even with decreases in HACU. Pharmacologic doses of rhNGF can further augment ChAT activity in damaged cholinergic neurons, showing the usefulness of exogenous NGF even when endogenous NGF is elevated in response to injury. 相似文献
6.
D. V. Sinicropi A. Dombrowski C. W. Montgomery R. K. Evans F. C. Kauffman 《Journal of neurochemistry》1980,34(5):1280-1287
Abstract: Concentrations of selected intermediates of energy metabolism whole rat superior cervical ganglia maintained in vitro by an organ culture technique were compared with values measured in small slices of this maintained under essentially the same conditions. Rates of incorporation [3 H]leucine into trichloroacetic acid-precipitable material in whole ganglia mained constant for at least 48 h: however, the oxidation-reduction state tissue as indexed by (NAD):(NADH) ratios calculated from measured amounts of lactate and pyruvate decreased more than 50% within 3 h in vitro . Ganglion explants prepared by cutting the tissue into 300 -pm transverse sections played (NAD):(NADH) ratios that were about three times greater than noted in whole ganglia maintained in vitro for the same period of time. explants contained significantly higher concentrations of pyruvate and α-ketoglutarate than whole ganglia maintained in culture. Maintenance of vorable metabolic state may support the extensive growth of neurites seen explant cultures of superior cervical ganglia. Outgrowth of processes containing catecholamines could be detected readily in explant cultures of ganglia adult rats; however, this was somewhat slower and less consistent than growth observed in explants from neonatal rats. Outgrowth of neurites adult ganglia was minimal without the addition of Nerve Growth Factor. 相似文献
7.
Paolillo , Dominick J., Jr ., and Ernest M. Gifford , Jr . (U. California, Davis.) Plastochronic changes and the concept of apical initials in Ephedra altissima. Amer. Jour. Bot. 48(1): 8–16. Illus. 1961.—The occurrence of distal mitoses and the differentiation of derivatives of the distal cells of the apex of E. altissima are correlated with stages of the plastochronic cycle. The relative rates of growth of elements within the various regions of the apex are characterized in terms of elongation gradients. The numbers of mitoses found in median sections of individual apices are recorded. It is concluded that the distal zone is the source of all other cells of the apex and should be regarded as a zone of initials. The concept of “méristème d'attente” and “anneau initial” is discussed in relation to the observations made on E. altissima. 相似文献
8.
Ammonium ion induces phenovariation in Gymnocolea inflata (Huds.) Dum. (Lophoziaceae) similar in nature to that induced in representatives of four other families of leafy liverworts by antagonists of hydroxyproline-protein metabolism. That is, in the presence of ammonium ion, ventral leaves developed and the lateral leaf morphology and the branching pattern of the plants changed. These changes, which reflect altered patterns of morphogenesis, were correlated with statistically significant (P ≥ 0.01) differences in peptidyl-hydroxyproline between normal and NH4+-induced phenovariant plants. The results support the hypothesis that cell wall-associated hydroxyproline-protein plays a morphoregulatory role and that any of a number of factors, genetic, epigenetic or environmental, that could alter the synthesis/distribution of this moiety could cause changes in form. 相似文献
9.
Teer Eman Joseph Danzil E. Dominick Leanne Glashoff Richard H. Essop M. Faadiel 《中国病毒学》2021,36(5):1133-1143
Virologica Sinica - Although antiretroviral treatment lowers the burden of human immunodeficiency virus (HIV)-related disease, it does not always result in immunological recovery. This manifests as... 相似文献
10.
Pretreatment of spinal cord with ethylene glycol permits long-term storage of the tissue at -70 degrees C prior to isolation and biochemical analysis of the cell bodies of spinal motoneurons. The method is useful for storing spinal tissue from laboratory animals, as well as from human post mortem specimens, where aliquots of tissue may then be used for motoneuron isolation over an indefinitely long period. In addition to inhibiting the loss of soluble proteins from the neurons during freezing and thawing, cryoprotection increases the yield and improves the appearance of the isolated cell bodies. The method should aid biochemical studies of many kinds of neuronal subpopulations isolated from small amounts of starting material. 相似文献